Wyniki wyszukiwania - BazTech

1

Effect of biodiesel on the development of split injection characteristics

Slavinskas Stasys, Labeckas Gvidonas, Mickevičius Tomas

Combustion Engines

|

2019

|

R. 58, nr 2

103--107

EN

The paper presents the experimental test results of a common rail injection system operating with biodiesel and the diesel fuel. The three fuel split injection strategies were implemented to investigate the effects made by biodiesel and a fossil diesel fuel on the history of injector inlet pressure and the injection rate. In addition, the three intervals between split injections and the different injection pressures were used to obtain more information about the studied subjects. The obtained results showed that the peak mass injection rates of the main injection phase were slightly higher when using biodiesel than the respective values measured with the normal diesel fuel. Because the first injection phase activated the fuel pressure fluctuations along the high-pressure line and in front of the injector, the time-span between injections has an impact on the injector inlet pressure and thus the fuel injection rate during the second injection phase. Since the nozzle closes little later for biodiesel, the injector inlet pressure also occurred latter in the cycle.

2

Investigation of acoustic emission response and fracture morphology of rock hydraulic fracturing under true triaxial stress

Yue Yuqing, Peng Shoujian, Liu Yixin, Xu Jiang

Acta Geophysica

|

2019

|

Vol. 67, no. 4

1017--1024

EN

Hydraulic fracturing technique has been used to exploit hydrocarbons resources in the past years. To investigate the mechanism of hydrofracturing process, a true triaxial hydraulic fracturing device combined with acoustic emission (AE) system is employed to study the crack initiation and propagation under different injection rates. Furthermore, a 3D scanner is employed to obtain the morphology of the fractured surface when the fracturing test completes. The results show that in hydraulic fracturing, the cracks propagating mostly perpendicular to the direction of the minimum horizontal principal stress. A lower injection rate corresponds to the peak value of the AE count occurring at a later time and a large value of the cumulative AE count, indicating greater damage and a complicated crack propagation path. With the injection rate increased, the earlier the microcracks occur, the shorter the fracturing time of the specimen is, and the fatter the fracture morphology.

3

Experimental study on injection characteristics of diesel-bioethanol fuel blends

Slavinskas S., Mickevičius T.

Combustion Engines

|

2015

|

R. 54, nr 2

28--32

EN

This article presents the test results of injection processes of diesel-bioethanol fuel blends on a high pressure common rail injection system. The injection characteristics were analyzed using the injection rate measuring instrumentation. The injection rate, cycle injection quantity, injection delay and injection duration were analyzed across a range of injection pressure and injection energizing time. As the results show, the peak injection rate and delay of diesel-ethanol blends are lower compared to diesel fuel. The injection duration and discharge coefficients of diesel-ethanol blends were lower than those of diesel fuel. It was observed that fuel density and fuel viscosity have significant influence on the injection characteristics.